Abstract: As artificial freezing technique has been widely used in the deep underground construction, more and more people have become aware of the necessity to carry out researches on mechanics of the deep frozen soils urgently. By analyzing the worldwide understanding of deep geotechnical engineering and previous understanding of deep soils and deep frozen soils, a new conception system is provided for the deep frozen soils and mechanics of the deep frozen soils considering the special characteristics of the formation process and stress of the deep frozen soils. The research content and methods are discussed to study the mechanics of deep frozen soils, and the developing status quo of the mechanics of deep frozen soils is presented. Finally, some urgent problems to be solved in this study task are put forward in terms of laboratory physical and mechanical tests, large-scale model simulations, theoretical model and engineering applications of deep frozen soil.